Throughout the United States, we are currently living in this in-between zone; just 6 months ago we stayed home to protect our families during the holidays, but now many of us are vaccinated and told masks and distance are no longer necessary. Yet, some epidemiologists are suggesting these new guidelines by the CDC came out too soon because not enough of us are vaccinated yet. Even if you’ve recovered from COVID-19, the vaccine can give you 10 times more antibodies than your natural immunity. So, with only 38% of the population vaccinated, are we ready to resume pre-pandemic activities?
Even if we were all vaccinated, would it be enough to end this pandemic? Various mutations of the virus have appeared, highlighting the possibility of even further and more deadly mutations, requiring a re-evaluation of the effectiveness of each vaccine; Pfizer, Moderna, Johnson and Johnson, AstraZeneca, etc. Hopefully, with our newfound speed in developing a new mRNA vaccine, we would be prepared when the vaccines are no longer effective. But they still take some time to develop and test before mass distribution.
The best protection would be to already be vaccinated from all possible variants before an outbreak emerges. A new pan-coronavirus vaccine developed at the Duke Human Vaccine Institute protects monkeys from a variety of coronavirus infections—including SARS-CoV-2, the B.1.1.7 variant (widespread in the UK), the B.1.351 variant (widespread in South Africa) SARS-CoV-1, and related bat coronaviruses that could fuel the next pandemic. But how is this possible?
Normally, when you get sick from a virus, your immune system builds antibodies to attack the virus that’s replicating in your body and to protect you if it comes back again. To do this, it finds something unique about the virus, so it can quickly identify it as foreign and tag it for your immune system to destroy (to learn more, see our earlier post on how vaccines work). The new pan-coronavirus vaccine considered all the SARS variants and bat coronaviruses together to find the one characteristic they all share. This allows the body to quickly identify it as foreign and destroy it when it enters the body.
To test the effectiveness of the pan-coronavirus vaccine, the scientists first injected monkeys with the vaccine and recorded antibody levels two days later. When given a booster shot, the antibodies grew even more, as expected. They then tested the blood plasma filled with antibodies and found that the antibodies did indeed identify the one specific target that is unique across all the variants: the binding site. They then needed to see if the antibodies attacked the virus. To do this, they took the blood plasma from the monkeys and tested it against a pseudovirus of SARS-CoV-2. As expected, the antibodies neutralized the virus. But even more exciting, the vaccine seems more effective at neutralizing the virus than 2 mRNA vaccinations (the typical regimen for Pfizer and Moderna vaccinations) or natural human infection. Tests against the SARS variants and bat coronaviruses (a threat for future outbreaks) also proved effective.
The scientists then infected monkeys with a SARS-CoV-2 challenge and found the vaccinated monkeys blocked COVID-19 infection by 100%. They had no detectable levels within 2 to 4 days after the challenge compared to control monkeys. And, when examining the lung tissue, they found reduced inflammation.
These results look very promising for developing a human pan-coronavirus vaccine that uses the same technology. Such technology could prevent, rapidly temper, or extinguish the next coronavirus threat to humans. Notably, this research is published as an “Accelerated Preview” in the journal Nature, so some content is liable to change before final publication.
–Speaking of Research